Abstract: A fluid leakage detecting element comprises a heat generating resistive member and a temperature compensating resistive member disposed on a substrate. Each of the resistive members is prepared in the form of a paste of a metal which has a high temperature coefficient and a high thermal conductivity and whose melting point is higher than the baking temperature of the substrate. These resistive members are printed in thick film form on the substrate which is sufficiently electrical insulating and has a high thermal conductivity.
Type:
Grant
Filed:
January 19, 1983
Date of Patent:
February 19, 1985
Assignee:
Hitachi, Ltd.
Inventors:
Yoshito Tanaka, Ken Ichiryu, Naohiko Iwata
Abstract: A semiconductor device comprising a semiconductor substrate having at least two resistor elements, wherein said resistor elements have a specific resistance ratio relative to each other, an insulation layer formed on a major surface of said semiconductor substrate, a circuit wiring layer formed on said insulation layer covering a portion of said insulation layer which corresponds to at least one of said resistor elements, and a dummy wiring layer made of the same material as that of the circuit wiring layer and formed on the insulation layer covering that portion of said insulation layer which corresponds to the resistor element or elements not covered by said circuit wiring layer, and where the ratio of an overlapping area of one resistor element in said circuit wiring layer and an overlapping area of the other resistor element and said dummy wiring layer is equal to a resistance ratio of said resistor elements.
Abstract: A new group of bulk polycrystalline materials which are capable of exhibiting, selectively, either memory switching or threshold switching. The body of the material, which can be molded into a suitable ceramic resistor configuration with ohmic electrodes and a sintered body composition, comprises as a majority proportion zinc oxide with the balance being another polycrystalline inorganic oxide such as bismuth oxide, cobalt oxide, chromium oxide, antimony oxide, praseodymium oxide, lanthanum oxide, holmium oxide and manganese oxide, or mixtures thereof.
Type:
Grant
Filed:
June 21, 1982
Date of Patent:
September 18, 1984
Assignee:
Iowa State University Research Foundation, Inc.
Inventors:
Orville Hunter, Jr., Joseph A. Schaefer
Abstract: A liquid level sensor having a pair of upright conductors spaced by an insulator defining a first high resistance path between the conductors. An electrically conductive path is interposed between the upright conductors at a discrete location at which liquid level is to be measured. It includes a liquid accessible gap of a dimension such that the electrical resistance across the conductor when the gap is filled with the liquid is detectably less than when the gap is emptied. The conductor might also be physically altered by temperature changes to serve also as an indicator of elevated temperature.
Type:
Grant
Filed:
January 29, 1981
Date of Patent:
September 21, 1982
Assignee:
The United States of America as represented by the United States Department of Energy
Abstract: A method of assembling an electrical device including current relay means having housing means with at least one female terminal disposed therein and at least one switch means terminal extending exteriorly of the housing means. In this method, a solid state device is disposed at least adjacent the housing means, and the solid state device is connected in circuit relation between the at least one female terminal and the at least one switch means terminal.
Abstract: An apparatus for cooperation with an existing opening within a cooling radiator of a vehicle for determining the liquid level in the radiator. The radiator, which may be an automobile or truck radiator, is connected to an electrical power source of the vehicle through the vehicle chassis. An insulator is established relative to the vehicle radiator in a substantially fixed relation. A sensor is mounted to the insulator for extending into the liquid in the radiator when a sufficient quantity of liquid is contained therein. The sensor has a plurality of curved surfaces for increasing the surface area of the sensor. An indicator interconnects the sensor with the electrical power source of the vehicle for indicating the level of liquid contained in the radiator by conductivity through the liquid in contact with the sensor. The increased surface area of the sensor enables the indicator means to be a conventional incandescent lamp connected in series with the sensor and the electrical power source of the vehicle.
Abstract: Anisotropically pressure-sensitive electroconductive composite sheets are provided which have a very low electric conductive resistance in the direction perpendicular to the plane of the sheet when compressed with an adequate pressure in the direction but a high insulating resistance in all directions within the plane of the sheet. The composite sheets are constructed so that electrically conductive fibers are uniformly dispersed in the matrix of an electrically insulating substance, the average length of the fibers ranging from 20 to 80% of the thickness of the sheet, and are aligned in the direction substantially perpendicular to the plane. They are useful as a switching material in various miniaturized electronic circuits.
Abstract: A device for monitoring the composition of the exhaust emission of a combustion process includes a hollow elongated body open at one end thereof and an elongated substrate located in the body and defining adjacent the one end of the body an exhaust emission sensing element and a resistive heating element. The sensing element and the heating element are printed on opposite sides of one end of the substrate and are electrically connected to respective first conductive areas extending to the opposite end of the substrate. A carrier is mounted in the other end of the body and supports at least two terminal members which are electrically connected to respective second conductive areas provided on first and second elongated, flexible circuit elements which at their free ends project from the carrier and are folded inwardly so that said second conductive areas are presented to each other.
Type:
Grant
Filed:
April 3, 1978
Date of Patent:
March 18, 1980
Assignee:
Lucas Industries Limited
Inventors:
Christopher V. Cullingford, Martin A. Read
Abstract: The amount of solid carbon deposited on a surface by a gas during the coking cycle in a coke oven is determined by measuring the thickness by electrical resistance readings, as a function of time, of carbon deposited on a probe passing through the roof of the oven and into the path of the gases flowing out of the oven.
Abstract: A semiconductor transducer comprises a semiconductor strain gauge composed of a mono-crystalline semiconducting material and a strain sensing region formed in a first main surface of the mono-crystalline semiconducting material, and a strain measuring member coupled to the semiconductor strain gauge through an alloy material. An electrical insulating layer is attached to a second main surface of the mono-crystalline semiconducting material which is coupled to the strain measuring member through the alloy material. The insulating layer is extended to a side surface of the mono-crystalline semiconducting material thereby to cover the same side.
Abstract: A corrosion detector for indicating when a transportation vehicle such as an aircraft, train, truck, bus, automobile, or the like, should be washed. The detector indicates the amount of corrosive contamination collected on the vehicle's metal surface. The detector measures the electrical resistance in a chemical solution formed when a water saturated filter paper is placed on the metal surface.
Abstract: In a catalytic method for selectively detecting carbon monoxide in the presence of hydrogen in an oxygen-containing atmosphere, such as may be used in monitoring exhaust gases from combustion processes, the catalyst is a platinum-rhodium alloy containing not less than about 10% rhodium. The catalyst is maintained at a temperature such that it will cause combustion of carbon monoxide but will not readily cause combustion of hydrogen, the thermal effect on the catalyst resulting when a test atmosphere is brought into contact with it being sensed to provide a measure of the carbon monoxide concentration in that atmosphere.
Type:
Grant
Filed:
May 28, 1975
Date of Patent:
July 19, 1977
Assignee:
National Research Development Corporation
Inventors:
David Keith Brown, David William Dabill, Jack Graham Firth, Alan Jones, Thomas Alwyn Jones
Abstract: A semiconductor sensor for fluids comprised of a body composed of an inorganic semiconductor material which is provided with a drain and source zone interconnected by a channel zone and including a layer of a reactive organic material capable of forming a reversible bond with at least a portion of the fluid being detected in the vicinity of the channel zone between the source and drain zones. The reactive organic material, such as carotenoids, polypropylenes, phthalocyanines, etc. reversably interacts with molecules of a given fluid substance and produce a reversible change in the surface potential of the layer composed of the organic material via a field effect and thus produce a reversible change of resistance in the channel zone and indicates the presence of such fluid by a change in the drain current of the sensor.
Abstract: Conductive polymer having a steeply-sloped positive temperature coefficient (PTC) of resistance with a sharply defined anomaly temperature is provided by selecting a polymer having crystalline structure at room temperature, a glass transition of approximately 13.degree.F. or lower and a narrow molecular weight distribution as measured by a flow ratio of less than 9 or a melting point range of 30.degree.C. or less. The polymer is filled with conductive particles and may include additional additives such as stabilizing agents and flame retardants. The ingredients are mixed, subjected to shearing forces and then formed into the desired configuration. The maximum permissible processing temperature is identified for the specific polymers employed.
Abstract: A heavy duty PTC resistor with a pressed and sintered hollow cylindrical body of a ceramic composition which has two end faces in a radial plane with a connection contact on each end face.A heavy duty PTC resistor sintered body of a ceramic composition which has two end-faces carrying a connection contact; the invention also concerns a method of manufacturing such PTC-resistor.High duty PTC-resistors are required for some purposes. If for example a PTC-resistor is used as a starting device for a single-phase motor, it has to be designed to deal with almost the entire mains voltage and to carry power of 500 W or more. The usual cylindrical bodies, provided at their two end-faces with connection contacts, frequently exhibit cracks under loads of this kind.A high-duty PTC-resistor is thus known (German Patent Specification OS 1 465 349) which is made up of a stack of solid or hollow flat cylindrical discs, the end-faces of the superposed discs being interconncted by a contact layer.
Abstract: In semiconductor integrated circuits, piezoresistance is recognized as a factor affecting production yield and circuit performance. Current flow in a circuit resistor is aligned with one of the <100> family of equivalent directions. When current is flowing along such a direction the change in resistance due to any combination of stress components is at a minimum. Additionally, variation of resistance due to stress and strain may be reduced by an increase of the total impurity concentration in a resistor.
Type:
Grant
Filed:
December 27, 1974
Date of Patent:
June 22, 1976
Assignee:
Bell Telephone Laboratories, Incorporated
Abstract: A system for simulating the insertion of electric resistance values of either positive or negative quantity into an electric circuit and for cancelling drift errors therefrom.
Type:
Grant
Filed:
January 3, 1975
Date of Patent:
March 30, 1976
Assignee:
The United States of America as represented by the United States Energy Research and Development Administration